One thing I learned is that an easy 300k is easier than a hard 200k. The significance is that, if you were not just totally wiped out at the end of your 130 mile ride, you're ready for a 200 miler right now, if things go right.

When I did my first 300k ride, I had done maybe a dozen or more 200k's. The 300k was a breeze, winds were favorable, I just flew. But then several months later, I did another 300k, and this one involved cranking into a headwind for the last 90 miles. I did one 600k where the winds were non-existent one way and a tailwind the other way, I was in a big group, and I averaged as fast as I've ever done on any ride. But then I've done some long rides in the heat where they just turned into a death march. Part of the benefit of riding is getting your legs and lungs in better shape, but part of the benefit is learning to deal with different problems that come up.

Anyway, back to the topic, if you do a bunch of riding, you'll probably start having reliability issues at some point with a cheap bike, and so the bike question will sort of answer itself for you. If you're just planning one 200-miler and then quit forever, it would probably be just as well to try it on that bike.